LODI, Wis. -

A motorcyclist died and a passenger was injured in a crash on Saturday.

The Columbia County Sheriff's Office said that a motorcycle crashed on County Highway VJ, near Richards Road in Lodi Township, about 6:30 p.m.

The driver was taken to the University of Wisconsin Hospital in Madison by Med-Flight and died at the hospital. Authorities said the passenger was taken by ambulance to UW Hospital with injuries.

Authorities said neither person was wearing a helmet. Both people were from rural Lodi.

Authorities identified the motorcycle driver who died as James D. Birkes, 49.

Investigators don't believe alcohol was a factor in the crash, but they said speed may be a factor, according to a Columbia County Sheriff's Office news release.

The Columbia County Sheriff's Office is continuing to investigate the crash.